Two-piece bogie with a novel suspension system

ABSTRACT

The subject matter invention is a two-piece bogie utilized in low floor railed system vehicles and having wheel sets; carrier parts which are provided mutually by being connected to each other through a hinged connection and which are positioned on the wheel systems where the wheel sets are provided; seating parts embodied in the carrier parts; wherein the seating part comprises a wall part with a placement height determined according to a wheel radius; and a placement plate embodied at the continuation of the wall part, in order to provide isolation of the noise and vibrations occurring in two-piece and low floor bogies.

TECHNICAL FIELD

The present invention relates to a two-piece bogie isolating noise and vibration in low-floor railed system vehicles and improved for providing a balanced structure to the vehicle.

PRIOR ART

Because of the traffic problems particularly faced in big cities, railed systems are used in a more widespread manner. Railed systems can be classified as light rail systems, heavy rail systems, automatic systems, single rail systems and magnetic levitation systems. Among said systems, except the magnetic levitation system, vehicles have wheels; and vehicles are moved on the rails using said wheels. In local transportation, mostly light rail systems are utilized, and less frequently, heavy rail systems are utilized. As an example to light rail systems, trams and light subway trains can be given as example. These kinds of railed systems are the low-floor or high-floor systems. In light rail systems, on the rails, there is a single vehicle or there are vehicles which are in connection to each other in short sequences.

In local transportation, all of the railed system vehicles, which have wheels, comprise wheel systems, body, bogie, and suspension systems placed in between. Bogie, which is among the components forming railed system vehicles, carries out the most important function for the dynamics of the vehicle. The bogie provides the wheel movements and at the same time it carries the remaining components of the vehicle. Besides, the most important function of bogie is to provide flexibility in the structure by eliminating the rigid structure existing between the wheel axle shafts and the body during the non-linear movements of vehicles or during the movements of vehicles on deformed rails.

In addition, today, the abovementioned high floor railed systems are used frequently. However, the usage of said high floor railed system vehicles by patient and old people leads to some problems. As an alternative to high floor railed system vehicles, low floor railed system vehicles are used, and the height of these low floor railed system vehicles is generally up to 35 cm, and passengers can easily access the railed system vehicles without the need for a ramp or for a staircase. However, in said low floor railed systems, some problems are faced. Since low floor is used, the vehicle wheels should be made smaller. If the vehicle wheels are made smaller, in cases where the vehicle follows a curved route, vibration occurs because of the lateral forces occurring in the vehicles. Moreover, the noise produced by the vehicle increases and because of said noise and said vibration, the comfort of the passengers and of the driver is deteriorated.

By means of the flexibility provided to the structure by the bogies, the vibrations of the vehicle are decreasing and the comfort of the vehicle increases both for the passengers and also for the operator. Moreover, the load applied to the chassis is decreased thanks to the flexibility of the structure and thereby metal fatigue is minimized, and the abrasions occurring in the rails and in the wheels are decreased. In addition, since the bogie comprises two flexible pieces, even if the rails are deformed in the vertical direction, the connection of the wheels on the rail is not interrupted and thus the risk of derailing is decreased.

Bogies can be classified in two classes, namely, classical bogies and advanced bogies. Classical bogies comprise a rigid frame and thus they cannot provide the flexible structure required for the railed system vehicles which particularly move on non-linear paths. The advanced bogies have various designs, and the most important difference between the advanced bogies and the classical bogies is that the advanced bogies comprise two frame pieces and these pieces are connected to each other by means of flexible members.

In railed systems, vibration comfort is improved and depending on this, the noise formation and the negations in the passenger and driver comfort are eliminated by means of the selection of a suitable bogie, and additionally, by means of the usage of bogies with advanced suspension systems. By means of a suitably designed suspension system, higher performance criteria can be provided depending on the changing load and road conditions. In bogies, generally passive suspension systems are used and said suspension systems comprise two parts. One of these parts is the primary suspension connecting the wheel system to the bogie frame and the second one is the secondary suspension positioned between the bogie frame and vehicle body.

The primary suspensions comprise rubber pads. The positions of the primary suspensions on the bogie are fixed, and the main function thereof is to dampen the vibrations between the wheels and the bogie. The secondary suspensions are the air springs which are generally called “bellow”. Air springs are structures formed by covering a bearing by an elastic rubber sheath and having gas therein. The dimensions of the air springs are small and they preserve the driving height and they provide vibration and noise insulation in order to eliminate the disadvantages faced in the low floor bogies. They have an important role in keeping the vertical position of the vehicle in a fixed position. The positions of the secondary suspensions on the bogies are changeable.

In the patent application CN2515075, a system is disclosed where the secondary suspension exists at the center of the bogie and where there is only one bogie. In this case, the suspension is close to the weight center of the vehicle; however, a single suspension system is not sufficient for the dampening process. Besides, as disclosed in the patent application JP2003025989, there may be pluralities of secondary suspensions. This provides sufficient dampening effect, and since the suspensions are provided at different positions on the bogie, deviation from the weight center of the vehicle occurs and the driving comfort is deteriorated. Moreover, since the bogie structures described in said patent applications are rigid structures, the movement of the railed system vehicle is limited, and the flexibility of said bogies is at a low level.

In order to provide a solution to the abovementioned problems, the applicant has a patent application 2011/07418. In said application, a two-piece bogie structure is disclosed in order to provide flexibility to the bogie structure and in order to decrease the vibrations occurring in the railed system vehicles. However, since the flexibility provided by said bogie is insufficient for increasing vibration comfort, the application numbered 2011/07418 is improved for providing increase in vibration comfort.

As a result, by means of the improvements provided by the novel functions to be added to the two-piece bogie application, the novel system, disclosed in the patent application 2011/07418, will be much more effective.

BRIEF DESCRIPTION OF THE INVENTION

The present invention relates to a two-piece bogie improved for isolating noise and vibrations occurring during the movements of low floor railed system vehicles, in order to eliminate the abovementioned problems and to bring new advantages to the related technical field.

The main object of the present invention is to provide a two-piece bogie having suspensions corresponding to the weight center of the vehicle, in order to be used in low floor light railed system vehicles like trams which are moving on non-linear rails and which are particularly used in city centers.

Another object of the present invention is to provide a two-piece bogie providing the engines to be positioned next to the bogie, in low floor railed system vehicles.

Another object of the present invention is to provide a two-piece bogie where big wheels can be used so as to decrease the vibrations in low floor railed system vehicles.

Another object of the present invention is to provide a bogie where the loads applied by the body are transmitted directly to the rails by means of the wheels without forming any momentum in order to reduce wheel abrasions.

In order to realize all of the abovementioned objects and the objects which are to be obtained from the detailed description below, the present invention is a two-piece bogie utilized in low floor railed system vehicles and comprising wheel sets; carrier parts provided mutually by being connected to each other through a hinged connection and positioned on the wheel systems where said wheel sets are provided; seating parts embodied in said carrier parts; and secondary suspensions positioned on said seating parts. Accordingly said bogie is characterized in that said seating part comprises a wall part with a placement height determined according to a wheel radius so as to provide positioning of the wheel sets under the seating parts; and a placement plate embodied at the continuation of said wall part and providing positioning of said secondary suspensions on the wheel sets, in order to provide isolation of the noise and vibrations occurring in two-piece and low floor bogies.

In a preferred embodiment of the subject matter invention, said seating parts are provided on the four symmetrical corners of the bogie so that the seating parts are provided on each wheel set.

In another preferred embodiment of the subject matter invention, in order to provide balanced distribution of the loads applied on the seating part, there is a connection arm embodied so as to extend at the continuation of the wall part and so as to provide connection of the said wall part to the seating part.

In another preferred embodiment of the subject matter invention, said seating part comprises a recess part wherein the axle shaft is placed and embodied at the wall part in a manner that the seating part seats on the axle shaft provided in the wheel system.

In another preferred embodiment of the subject matter invention, there are housings which are embodied on said placement plate and wherein the second suspension is placed.

In another preferred embodiment of the subject matter invention, at the lower end of said wall part, there are housings wherein the first suspensions are placed and which are embodied at the two sides of the recess part.

In another preferred embodiment of the subject matter invention, said placement height of the wall part is at a value equal to the height from the center of the axis, where the wheel set extends, to the bottom surface of the placement plate.

In another preferred embodiment of the subject matter invention, said placement height is determined according to the maximum wheel radius utilized in the low floor railed system vehicle.

In another preferred embodiment of the subject matter invention, said placement plate is embodied so as to be substantially parallel with respect to the wheel systems.

BRIEF DESCRIPTION OF THE FIGURES

In FIG. 1, the general view of subject matter two-piece bogie is given.

In FIG. 2, a top perspective view of the subject matter bogie is given.

In FIG. 3, the detailed view of the subject matter two-piece bogie is given.

In FIG. 4 a, the lateral cross sectional view of the subject matter bogie is given.

In FIG. 4 b, another lateral cross sectional view of the subject matter bogie is given.

In FIG. 5, another frontal cross sectional view of the subject matter bogie is given.

REFERENCE NUMBERS

10 Bogie

20 Carrier Part

-   -   21 Hanger Bar     -   22 Connection Bar         -   221 Connection Region         -   222 Assembly Part     -   23 Seating Part         -   231 Connection Arm         -   232 Wall Part         -   233 Recess Part         -   234 Placement Plate         -   235 Connection Extension         -   236 Housing         -   237 Housing     -   24 Engine Housing

30 Carrier Part

-   -   31 Hanger Bar     -   32 Connection Bar         -   321 Connection Region         -   322 Assembly Region     -   33 Seating Part         -   331 Connection Arm         -   332 Wall Part         -   333 Recess Part         -   334 Placement Plate         -   335 Connection Extension         -   336 Housing         -   337 Housing     -   34 Engine Housing

40 Beam

-   -   41 Connection Extension     -   42 Connection Pin

50 Primary Suspension

60 Secondary Suspension

70 Wheel System

-   -   71 Axle Shaft         -   711 Connection Sidewall         -   712 Placement Part     -   72 Wheel Set

h: Placement Height

r: Wheel Radius

THE DETAILED DESCRIPTION OF THE INVENTION

In this detailed description, the subject matter bogie (10) is explained with references to examples without forming any restrictive effect in order to make the subject more understandable. Accordingly, by means of the subject matter two-piece bogie (10) having a novel type of suspension system, the noise and the vibration occurring in the low floor railed system vehicles can be isolated.

The bogie (10), whose general view is given in FIG. 1, comprises two carrier parts (20, 30) provided in a mutual manner and beams (40) connecting said carrier parts (20, 30) to each other. While the wheel systems (70) are being positioned under the bogie (10), the vehicle chassis is placed thereon. The secondary suspensions (60) are positioned between the vehicle chassis and the bogie (10). The primary suspensions (50) are provided between said wheel systems (70) and the bogie (10).

The carrier parts (20, 30) essentially comprise a hanger bar (21, 31), and a connection bar (22, 32) provided so as to be substantially parallel with respect to said hanger bar (21, 31) and whereto said beams (40) are connected. There are seating parts (23, 33) at the ends of said hanger bar (21, 31) and of said connection bars (22, 32). The gap formed between the hanger bar (21, 31), the connection bar (22, 32) and said seating part (23, 33) defines an engine housing (24, 34). The seating parts (23, 33) comprise connection arms (231, 331) provided on the connection bar (22, 32); a wall part (232, 332) embodied defining a placement height (h) so as to extend at the continuation of said connection arms (231, 331); a placement plate (234, 334) embodied in a substantially parallel extending manner to the extension axis of the beams (40) at the continuation of said wall part (232, 332); and a connection extension (235, 335) which connects the hanger bar (21, 31) to the seating part (22, 32). A recess part (233, 333) is embodied at the bottom end of said wall part (232, 332). There are housings (237, 337), wherein said primary suspensions (50) are positioned, provided under the wall part (232, 332) at both sides of said recess part (233, 333). On said placement plate (234, 334), housings (236, 336) are embodied wherein the secondary suspensions (60) are positioned. On the connection bars (22, 32), there are connection regions (221, 321) provided in the same extension axis with each other and there are assembly regions provided in inverse symmetric positions on the connection bars (22, 32) with respect to each other.

The subject matter bogie (10) is a two-piece bogie and the carrier parts (20, 30) are connected to each other through said beams (40). The beams (40) are embodied in the same manner. A connection extension (41) is embodied at one end part of the beams (40) and a connection pin (42) is provided at the other end part. The connection of the beams (40) to the carrier parts (20, 30) is provided by the placement of said connection extensions (41) to said assembly parts (222, 322) and by the placement of said connection pins (42) to said connection regions (221, 321). The connection extensions (41) and the connection pins (42) provided on a beam (40) are positioned on the carrier parts (20, 30) provided mutually.

The wheel system (70) essentially comprises an axle shaft (71) and wheel sets (72) having wheels, which are connected to the axle shaft (71) and whose radius is equal to r, at both ends of said axle shaft (71). The axle shaft (71) comprises a placement part (712) extending at the continuation of the axle shaft (71) and accommodating a greater width than the width of the axle shaft (71), and a connection sidewall (711) provided at the continuation of the axle shaft (71) in the middle of said placement part (712).

The wheel systems (70) are positioned under the bogie (10). This positioning is provided so that the wheel sets (72) correspond under the mutual seating parts (33) at the carrier part (20, 30). The wheel sets (72) are placed under the placement plate (234, 334) and the axle shafts (71) are extending between the two carrier parts (20, 30) so as to exist in an extension axis which is substantially parallel to the extension axes of the beams (40). The positioning of the axle shafts (71) between the carrier parts (20, 30) is provided by the connection of the connection sidewalls (712) to said recess parts (233, 333).

As a result of the connection of the bogie (10) and of the wheel systems (70) to the chassis of the railed system vehicle, the seating part (23, 33) of the bogie (10) and axle shaft (71) in the wheel system (70) are seated completely onto each other thanks to the structures thereof, and a railed system vehicle which has a 100% low floor is provided. In addition, since the bogie (10) is embodied in a two-piece manner and since the connection between the beams (40) and the carrier parts (20, 30) provides movement, a flexible bogie (10) is provided. The wheel diameters of the wheel sets (72), provided in present low floor railed system vehicles, are small. This leads to more noise and vibration of the railed system vehicle during driving of the railed system vehicle. As the wheel diameter is made bigger, a decrease in noise and vibration formation is obtained in the two-piece bogie (10). The wheel diameter is made bigger in an adjusted manner thanks to the form of the seating part (23, 33). In this form, the placement height (h) of the wall part (232, 332) is determined taking the maximum wheel radius (r) into consideration.

The secondary suspensions (60) are positioned so as to correspond to a position on the wheels in said housings (236, 336) provided on the seating parts (23, 33). This provides the secondary suspensions (60) to be approached to the weight center of the railed system vehicle and leads to an increase in the vibration comfort. In addition, since the secondary suspensions (60) are provided at a position on the wheels, saving from space on the bogie (10) is provided. This provides the engines, which cannot be positioned under the railed system vehicles comprising low floor and two-piece bogie (10), to be positioned in said engine housing (24, 34) on the bogie (10).

The protection scope of the present invention is set forth in the annexed Claims and cannot be restricted to the illustrative disclosures given above, under the detailed description. It is because a person skilled in the relevant art can obviously produce similar embodiments under the light of the foregoing disclosures, without departing from the main principles of the present invention. 

1. A two-piece bogie used in low floor railed system vehicles: comprising wheel sets; carrier parts which are provided mutually by being connected to each other through a hinged connection and which are positioned on the wheel systems where said wheel sets are provided; seating parts embodied in said carrier parts; and secondary suspensions positioned on said seating parts, wherein said seating part comprises a wall part with a placement height determined according to a wheel radius so as to provide positioning of the wheel sets under the seating parts; and a placement plate embodied at the continuation of said wall part and providing positioning of said secondary suspensions on the wheel sets, in order to provide isolation of the noise and vibrations occurring in two-piece and low floor bogies.
 2. The bogie according to claim 1, wherein said seating parts are provided on the four symmetrical corners of the bogie such that the seating parts are provided on each wheel set.
 3. The bogie according to claim 1, wherein in order to provide balanced distribution of the loads applied on the seating part, there is a connection arm embodied so as to extend at the continuation of the wall part and so as to provide connection of the said wall part to the seating part.
 4. The bogie according to claim 1, wherein said seating part comprises a recess part wherein the axle shaft is placed and embodied at the wall part in a manner that the seating part seats on the axle shaft provided in the wheel system.
 5. The bogie according to claim 1, further comprising housings embodied on said placement plate and wherein the second suspension is placed.
 6. The bogie according to claim 1, wherein at the lower end of said wall part, there are housings wherein the first suspensions are placed and embodied at the two sides of the recess part.
 7. The bogie according to claim 1, wherein said placement height of the wall part is at a value equal to the height from the center of the axis, where the wheel set extends, to the bottom surface of the placement plate.
 8. The bogie according to claim 7, wherein said placement height is determined according to the maximum wheel radius utilized in the low floor railed system vehicle.
 9. The bogie according to claim 1, wherein said placement plate is embodied so as to be substantially parallel with respect to the wheel systems. 